智能化地共享和复用地球观测应用实践所形成的知识，有序促进应用要素的高通量流动，是激活和释放地球观测系统效能的关键。地球观测知识枢纽(Earth Observation Knowledge Hub, EOKH)将分散的应用要素有机耦合，形成专题知识集合的协同设计与吞吐能力，是地球观测成果治理与智能服务的研究前沿。针对地球观测组织(Group on Earth Observations, GEO)发展GEO知识枢纽(GEO Knowledge Hub, GKH)得到的启示，结合地球观测知识本体研究最新进展，系统解析了EOKH的内涵与特征，梳理了发展EOKH的技术需求与挑战，分析存在的关键问题及其应对策略。在此基础上，提出了EOKH系统架构原型，结合地球观测知识包转移复用和知识推理2个EOKH典型应用场景进行了原理实现与概念验证。最后，就如何促进地球观测知识“人机物”要素的协同共生，提出了我国发展EOKH的相关认识与思考。文章认为，探索“人在回路”的高通量知识协同生产与转移技术，以及“知识驱动”的成果复用技术，是提升地球观测隐性知识可解释性、促进EOKH服务质量与发展力的必要举措。

Objective Intelligently sharing and reusing the knowledge developed by application practices are the keys to break through technical barriers and fully activate and release the effectiveness of Earth observations (EO). The Earth Observation Knowledge Hub (EOKH), which is used to organically couple decentralized knowledge bases, is a research frontier for the governance and intelligent service of global EO applications. In the design of Group on Earth Observations (GEO), the GEO Knowledge Hub (GKH) is intended to provide authoritative, validated and reproducible content for evidence-based reporting on policy commitments and decision making. Thus, The GKH offers a platform for users to discover, learn about and employ methods, analytical tools and applications; it also provides opportunities for the GEO community to collaborate and provide mutual assistance related to GKH contents. However, important lessons have learned during the implementations, such as the sensitive issue of intellectual ethics, and how to profit GKH from the recent technological advances in information technologies. In response to the problems and insights encountered by GEO in developing GKH, we systematically analyzed the connotation and characteristics of EOKH, sorted out the fundamental needs and challenges for the development of EOKH in China. Method Firstly, we systematically analyzed the connotation and characteristics of EOKH. The paper argues that EOKH is the intersection node of high-throughput trusted EO knowledge in knowledge sharing networks. It has 3 typical features, which are connectivity, high throughput and lightweight computing. Its core mission is to identify and transfer valuable research in a timely manner and to promote high throughput of application packages. Secondly, we sorted out the fundamental needs and challenges for the development of EOKH in China. Considering the latest progress in the study of EO ontology, we also analyzed the possible key technical problems and gave strategies to cope with them. On this basis, the system architecture prototype of EOKH is proposed which drawn on the system design concept of representational state transfer (REST), and an ontology model of conceptual EO knowledge and a formalization model of process-oriented EO knowledge are established. Result The paper argues that EOKH should be in an open collaborative environment where humans in the loop. The key technologies are system metrics, knowledge transfer, knowledge reuse, and knowledge exploration and visualization. Transfer and reuse of knowledge packages can greatly enhance the ease of development and reuse of EO application practices. Ontology modeling helps to formalize the intrinsic connection between the human-cyber-physical systems of EO application and enhances the interpretability of higher-order complex problems. Conclusion EOKH transforms knowledge sharing from point-to-point at element-level to group collaborative at system-level, which not only reduces the cost of cross-industry and socially integrated EO applications, but also avoids repetitive research inputs, helps break through technical barriers and cognitive obstacles, and releases the effectiveness of satellite digital economy services more comprehensively. The article argues that connecting the EO knowledge in the human-cyber-physical systems, exploring high-throughput knowledge co-production and transfer technology in a "humans-in-the-loop" environment are necessary to enhance the interpretability of tacit EO knowledge and promote the competitiveness and activeness of EOKH.